The present invention relates to anti-T cell receptor .gamma.-chain monoclonal antibodies which are useful as a reagent for investigating functions of T cell receptor .gamma.-chain.
T cells play an important role in the control of immune response and in cellular immunity, of the immune system. On its surface membrane, T cell has T cell receptors, which participate in performing the functions of T cell. Studies on the structure of the receptor using a monoclonal antibody obtained from a mouse immunized with cloned T cells have revealed that it consists of two polypeptides, .alpha.- and .beta.-chains. The sequence of the genes that encode these chains was determined by analysis based on molecular genetics. Tonegawa, et al. discovered a gene which encodes T cell receptor .gamma.-chain (hereinafter referred to as .gamma.-chain) as well as a gene coding for .alpha.- and .beta.-chains, but the role played by .gamma.-chain in the functions of T cells still remains uncertain. In addition, the presence of .delta.-chain linked to .gamma.-chain was also reported [Nature, 322, 145-149 (1986)].
To elucidate the functions of .gamma.-chain, an anlibody which specifically reacts with .gamma.-chain is required. Mouse-derived rabbit anti-.gamma.-chain antiserum has already been reported [Nature, 325, 720-723 (1987)], but no anti-.gamma.-chain monoclonal antibody has not been known so far.
Moreover, in order to perform a comprehensive and more detailed investigation on .gamma.-chain, a monoclonal antibody which has higher purity and specificity is needed.
The present inventors have found that monoclonal antibodies which react with .gamma.-chain can be produced by hybridomas obtained by fusing spleen cells of a DBA/2 mouse immunized with the .gamma.-chain of BALB/c mouse origin, which is expressed in Escherichia coli by recombinant DNA technique and murine myeloma cells, and have now completed the present invention.